One reason for the results: regulators who are actually on the ball, with a big assist from the watchdog press:

CFPB Director Richard Cordray this month vowed to take enforcement action against the debt-collection industry and said his agency will hold banks accountable for lapses by third-party debt buyers. The OCC has compiled a list of best practices for banks that sell third parties rights to collect credit card debts the banks have already charged off their own books. The agency said this month that it is developing more binding supervisory guidance for the industry.
New York State Superintendent of Financial Services Benjamin Lawsky also on Thursday proposed a series of reforms that would require debt collectors to improve recordkeeping and the disclosures they make to borrowers.

Ryan Chittum , a former Wall Street Journal reporter, is deputy editor of The Audit, CJR's business section. If you see notable business journalism, give him a heads-up at rc2538@columbia.edu.